1. Field of the Invention
This invention relates generally to the distribution of electric power and particularly to apparatus that operates an isolation switch in coordination with a circuit breaker with which it is used.
2. Background Information
The feeder circuits in an electric power distribution system are connected to a power source through power circuit breakers which provide protection and can isolate the feeder lines for maintenance. An isolation switch can be used in combination with the power circuit breaker to ground the feeder to assure that it is safe to work on. Where the isolation switch is provided on the line side of the circuit breaker, it is important that the circuit breaker be open when the isolation switch is being switched to the grounded position. The circuit breaker can then be reclosed to ground the feeder line for maintenance. It is important, therefore, to coordinate the operation of the isolation switch with that of the circuit breaker.
Ideally, the isolation switch is located adjacent the power conductors at the rear of the circuit breaker. In addition, multiple circuit breakers can be stacked one on a top of another and side-by-side in a switch gear assembly. Thus, little room is available for operating the isolation switches from the front of the switch gear assembly.